Exhaust from internal combustion engines (“ICEs”) generally includes various combustion by-products such as NOx, CO, or unburned hydrocarbons, for example. Federal and state laws generally require vehicles with ICEs to be equipped with devices to reduce tailpipe emission of these chemicals. One such device is a catalytic converter designed to convert harmful chemicals to less harmful chemicals, such as CO2, H2O, or N2, for example. This conversion is generally achieved by forcing exhaust gasses through the catalytic converter before exiting an exhaust system of the vehicle.
Catalytic converters generally include a porous catalyst brick, which can vary in overall size, but often have 400-900 cells per inch. Each cell includes a channel that runs the entire length of the catalyst brick and receives exhaust gas during use. As the exhaust gasses flow through the cells, some of the harmful chemicals react with the catalyst brick and are converted to less harmful chemicals. Over time, the ability of the catalyst brick to react with the exhaust gasses can decrease, which leads to increased tailpipe emissions and the need to replace the catalytic converter. Thus, vehicles are generally required to be equipped with on-board diagnostic (“OBD”) systems that indicate when the catalytic converter no longer performs as intended.
Vehicle manufacturers are required to test OBD systems to ensure their proper operation and to ensure proper vehicle emissions control. (For example, see: Title 13, California Code Regulations, Section 1968.2, Malfunction and Diagnostic System Requirements for 2004 and Subsequent Model-Year Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles and Engines (OBD II)). Manufacturers test an OBD system's ability to detect that a catalytic converter has reached a particular emission level by running the OBD system with an engine having a catalytic converter with an aged catalyst brick. Some methods of aging catalyst bricks and, thus, catalytic converters for such tests, include running an ICE with the catalytic converter for a predetermined time on a vehicle or a dynamometer. Another aging process includes exposing the catalyst brick to various chemical and/or thermal conditions in a laboratory setting.
Chemical/thermal aging of a catalyst brick typically includes saturating the catalyst brick with a corrosive liquid such as an acidic solution. For example, the channels within the catalyst brick may first be completely filled with a corrosive liquid. Once the liquid has completed its purpose, the liquid is then removed from the catalyst brick prior to performing the next step in the aging process, which may include thermal exposure or further chemical exposure.
Prior methods of removing the corrosive liquid from the catalyst brick channels include manually shaking the catalyst brick over a containment vessel, and/or allowing the catalyst brick to drip-dry, i.e. air-dry, while placed over an absorbent material. Due to the many small channels of the catalyst brick, it can be difficult and time consuming to remove the corrosive aging liquid from the catalyst brick and safely store the liquid until it can be properly disposed.